My Exchange calendar will only sync manually on my Galaxy S3. I want this to be automatic, like it is on the iPhone.

I've only had the S3 a few months, and I'm pretty sure it was syncing correctly when I first got it. I may have made a change to the settings over Xmas but I can't find what changed. I've deleted and re-added the Exchange account as well, to no avail.

Cybergangster: The Sync Calender is ticked on the accounts settings page.

But the MS Exchange ActiveSync page shows sync disabled?

sounds like you have turned sync off for all accounts in android system setting - easy why for me on 4.1.2 to check is to pull the the status menu (swipe down from the top) and there should be a sync icon on tool bar - is it green (ie sync on) or white (sync off)